John Kerr, one of the authors of Article 50 of the Lisbon Treaty which will be used by the UK to leave the EU, says that the Britain is set for a hard Brexit.

Lord Kerr of Kinlochard, as he is also known, believes that Britain will encounter difficulties because the debate surrounding Brexit is being driven by emotion, not evidence.

At a speaking engagement, the former chief British diplomat called for policy makers to make decisions based on evidence, rather than emotional arguments and popular opinion - he was commenting in particular on debate surrounding migration and Brexit.

PA

"I can't think of an example like Brexit where the government was working to a single aim that so few people in government actually believe in," he said at the talk which was attended by Business Insider.

"The argument that won the referendum was immigration but the problems faced by the NHS would be much greater if not for immigration. Migrants are less dependent on welfare than non-migrants. I feel sad that Labour is running away from these facts and feel like they need to make concessions," he continued.

"Supposing we did stop all immigration from the EU, we still wouldn't meet the off-the-cuff 100,000 net target David Cameron set as prime minister. We native Brits are so bloody stupid that we need injections of intelligence. Immigration is what keeps this country running. Evidence-based policy, please," Lord Kerr added.

He believes that if this emotional debate surrounding migration continues, things are going to get messy:

"[Theresa] May says controlling EU immigration is our primary goal, if that's the case, a soft Brexit isn't possible. We are heading for a hard and very unpleasant Brexit," Kerr said.